In a commercially available water bottle, there is generally provided with a straw assembly for convenience. For example, please refer to FIGS. 1 and 2, which are two side sectional views of a conventional water bottle-straw assembly, illustrating the cap of a lift-lower type used in the assembly is in an open and a closed states, respectively. The straw assembly essentially consists of a cap base 10 and a straw 20. The cap base 10 can be screwed to the open end of a water bottle 30, and a circular groove 11 is provided at the center of the cap base 10. A through hole 12 is fonned on the bottom of the circular groove 11. The cap base 10 is also provided with a cap 13 of a lift-lower type. The straw 20 goes through the through hole 12 of the circular groove 11 and is capped with a sucker 21. A spring 22 is disposed between the sucker 21 and the bottom of the circular groove 11 in such a way that the sucker 21 can be pushed up above the cap base 10 by the spring 22 when the cap 13 is in an open state as shown in FIG. 1, and that the sucker 21 can be pushed down into the circular groove 11 when the cap 13 is in a closed state as shown in FIG. 2. In addition, the lower end of the straw 20 generally approaches the inner bottom of the water bottle 30.
Although such a water bottle-straw assembly can provide convenience in water drinking, there are several drawbacks as described below.
Because the upper end of the straw 20 simply leads to the lower end thereof, the water sucked up in the straw 20 will flow back to the bottle 30 when a user's mouth no longer contains the sucker 21, resulting in that the air will immediately fill in the space above the water level in the straw 20. Consequently, when the user sucks again, he must completely suck the air in the straw 20 before the water in the bottle 30 comes up into his mouth through the straw 20. By the way, the lower the water level is, the more air is sucked. Users usually suck so much air into their stomachs that they may feel sick during or after drinking. When the cap 13 is in a closed state as shown in FIG. 2, it presses against the upper end of the sucker 21. However, since there is a gap between the sucker 21 and the circular groove 11, the water in the bottle 30 can leak out from the circular groove 11 through the through hole 12.
During sucking, users, especially children and babies, may be hurt at their teeth because the sucker 21 is usually made of hard plastics.
Furthermore, the straw 20 will move up and down as the sucker 21 moves up and down due to the opening and closing of the cap 13. Accordingly, it is usually a principle that the straw 20 is not so long and does not touch the inner bottom of the water bottle 30 when the cap 13 is in aclosed state, as shown in FIG. 2. Obviously, such a length of the staw 20 always makes a distance between the lower end of the straw 20 and the inner bottom of the water bottle 30 when the cap 13 is in an open state, as shown in FIG. 1. Therefore, users cannot completely suck the water out of the bottle 30, and there is always some water left in the bottle 30 after use.
Thus, there is a need to improve conventional water bottles for better sucking.